you can do it by: 1. using 3D-regional growing tool, which is labled as "3D Wand." in the "ROI" tab. or 2. draw 2D ROIs slice by slice using "OR" operation. hangyi >>> "[Seongjin]" <choisj70 at gmail.com> 03/12/09 10:07 AM >>> Is there anyone who know how to make 3D ROI in DTI Studio? Seongjin